Hang on a moment, buster.
Dear Word Detective: I am currently in a production of Gilbert and Sullivan’s “The Yeomen of the Guard.” One of the characters, Jack Point, commands a rowdy audience member to “hold thy peace and perpend.” It led to a minor discussion on the meaning of the word, which I originally thought meant “wait,” although I see now that the definition is “think carefully,” descending from root words meaning “to weigh.” One of the other cast members speculated on the connection to “perpendicular,” which looks to have descended from an Old English word that was, essentially, “perpendicular” with nothing prior. On another note, searching for “perpend” will also lead to reference to “perpend walls” which are created with “perpends” or “perpend stones,” which are stones which extend from the inner to outer walls. My guess would be that “perpend stones” grew from a shortening of “perpendicular” (since essentially that’s what they are, stones resting perpendicular to the direction of the wall to reinforce the construction), but I am far from an etymologist, of course. So, long question made short, what sort of a connection is there between “perpend” the verb, “perpend” the noun, and “perpendicular” the adjective, if any? — Sean Duggan.
Well, that is a long question, but the good news is that it’s long because you’ve done most of the explaining that’s needed to answer the question. In fact, I’m tempted to leave the room for a few minutes in hopes that my oh-so-smart computer will tie up the loose ends by itself (if it can tear itself away from sending my credit card numbers to Belarus, of course).
To begin near the beginning, the Latin verb “pendere” meant two things: “to weigh” and “to hang,” which makes sense since weighing things back then usually involved hanging them in some fashion, often on a balance scale with known weights on the other side. The Latin “pendere” lies behind many of our common English words today, including “pending,” “appendix,” “depend,” “impending,” “suspend,” “penchant,” “pendulum,” and even “penthouse,” originally a small “appended” structure alongside, and eventually atop, a building. (“Pent” as in “pent-up anger,” is a different word, a variant of “penned,” confined in a pen.)
The verb “perpend,” meaning “to ponder, to carefully consider,” first appeared in English in the mid-14th century, derived from the Latin “perpendere,” where “per” is attached to “pendere” as an intensive prefix, making the result “to weigh very carefully.” Our “perpend” is considered archaic today, although it still pops up on the cultural radar from time to time (“He perpends the advice and reflects that … their situation is both worse than ours and better,” 1994), and can be used both transitively and intransitively.
“Perpend” as a noun is simply a shortening of “perpendicular,” which appeared in English in the 15th century, originally meaning “vertical; at a right angle to the plane of the horizon” but now simply “at a right angle to a given plane, angle or surface.” The root of our “perpendicular” was the Latin “perpendicularis” (vertical) from “perpendiculum,” which meant “plumb line,” a weight on a string used by builders to determine a perfectly vertical line. You’re correct in your hunch that “perpend stones” are those set perpendicular to other stones to strengthen a wall. In fact, the only sense of “perpend” recognized by the Oxford English Dictionary as a noun is this masonry sense.
So “perpend” as a verb is closely related to “perpend” as a noun and “perpendicular” as an adjective, and they all hark back to that Latin “pendere.” But while “perpend” as a verb invokes the “weigh” sense of the Latin verb, as a noun (and in “perpendicular”) it draws more on the “hang” sense.